Properties of Benzene

Question 1

Benzene in cyclic and conjugated

Answer 1

True

Question 2

Benzene is unstable having a heat of hydrogenation 150 kJ/mol
less negative than a conjugated cyclic triene.

Answer 2

False. Benzene is unusually STABLE

Question 3

Benzene is planar and has the shape of a regular hexagon.

Answer 3

True

Question 4

Benzene does not undergoes substitution reactions and do not retain the cyclic
conjugation instead, does electrophilic addition reactions that would
destroy it

Answer 4

False. Benzene UNDERGOES substitution reactions that RETAIN the cyclic
conjugation RATHER than electrophilic addition reactions that would
destroy it.

Question 5

Benzene cannot be described as a resonance hybrid because its structure is not an
intermediate between two line-bond structures.

Answer 5

False. Benzene can be described as a resonance hybrid whose structure is
intermediate between two line-bond structures.

Question 6

Why is benzene less reactive?

Answer 6

p orbital overlaps equally well with both neighboring p orbitals

all six pi electrons are free to
move about the entire ring = RESONANCE

Question 7

a covalent bond in which electrons are shared

among more than two atoms

Answer 7

Delocalized bond-